This invention provides an improvement to the large-current radiator described in U.S. Pat. No. 4,506,267. The original radiator of that patent feeds energy to an antenna that radiates it. At certain times there is little or no radiation and the energy is dissipated in the active elements of the driving circuit; the active elements are typically transistors, light activated semiconductor switches (LASS), or electron tubes known as pulsatrons. The active elements must be designed to tolerate the largest dissipation of the energy. The need to dissipate rather than to radiate energy is a drawback for a number of reasons. A driving circuit is disclosed which drastically reduces the energy that needs to be dissipated.